THIN-FILM TL-BASED HTS MICROWAVE DEVICES

Linear microstrip resonators suffer from high peak current density ins ide the resonators which limit the power handling characteristics. To realise higher power filters for cellular applications it is possible to use two dimensional microstrip resonators (such as disks) to equali se the internal current distribution. We have designed and tested such microstrip resonators, fabricated from TBCCO 2212 thin films deposite d by RF sputtering onto 10x10mm and 20x20mm LaAlO3 substrates. The R-s of such Alms has been measured at 24 GHz using a sapphire dielectric resonator and shown to be less than 500 mu Omega scaled to 10 GHz and at 80K. Q values of 3-12 GHz disk resonators have demonstrated conside rable improvements when compared to both linear HTS microstrip resonat ors and comparable copper disk resonators. Additionally, the power han dling of such resonators has been shown to be superior to that of conv entional linear resonators fabricated from similar material.